Food and Drug Administration Commissioner Scott Gottlieb on Wednesday declared youth vaping an "epidemic," and said the agency will halt sales of flavored electronic cigarettes if the major manufacturers can't prove they are doing enough to keep them out of the hands of children and teens.

The FDA says it's giving manufacturers of Juul, Vuse, MarkTen XL, Blu and Logic 60 days to submit “robust” plans to prevent youth vaping. If the agency doesn’t think their plans go far enough, it could order their products off the market. Those five brands make up more than 97 percent of the U.S. market for e-cigarettes, FDA says.

The FDA is "reconsidering our overall approach" after a review of preliminary data on youth vaping, Gottlieb told USA TODAY.

"Teenagers are becoming regular users, and the proportion of regular users is increasing," says Gottlieb, a physician. "We’re going to have to take action."

More than 2 million middle school, high school and college students use the battery-powered devices to heat liquid-based nicotine into an inhalable vapor. E-cigarettes are by far the most popular tobacco product among teens: Nearly 12 percent of high school students and 3 percent of middle school students used the device in the past 30 days, according to the 2017 National Youth Tobacco Survey.

Some parents want the FDA to go farther.

Kelli Cogan says her 15-year-old son was able to get free Juul cartridges online last year by using his father's name and birth name and having them shipped to a different address. The Ohio woman says the company offered to block her husband's name from ordering, but she didn't think that was sufficient.

Juul spokeswoman Victoria Davis says the company now requires an age-verified signature on delivery and has made other changes to protect against distributing e-cigarettes to children under the legal vaping age in their states.

That's not enough for Jon Ahles of St. Paul, Minnesota.

"I have two teenagers that are now vape addicts," he says. "The first thing that the FDA needs to do is ban nicotine. These kids do not have a chance."​​​​​

The FDA's new approach is much faster than the rule-making process the agency announced in March. That was quickly criticized as too little, too late by public health advocates.

The brands will no longer be largely immune from regulations simply because they were already on the market in August 2016 when the FDA announced e-cigarettes would be regulated like other tobacco products.

Companies whose products were ordered off the shelves would have to show they have a net positive public health benefit before resuming sales.

The FDA also announced the results of its largest enforcement effort yet against e-cigarettes. The agency targeted more than 1,300 online and brick-and-mortar retailers with warning letters or civil penalties for selling to minors. Officials said 131 of the retailers will have to pay penalties.

Gottlieb told USA TODAY last month that the FDA was weighing the benefits of e-cigarettes in helping adults quit smoking against the risk to young people who become addicted to tobacco through vaping.

Many adults prefer flavored e-liquid when they are trying to quit. But Gottlieb now says he's prepared to make vaping less attractive to adults if it reduces the harm to teens.

Gottlieb said the agency could also target "cartridge-based products," such as the USB-sized Juul, which is favored by teens and sold in convenience stores. Adults tend to use bulkier "open tank" vaping products, he said.

A spokeswoman for Vapers United, a group that promotes vaping as a way to quit smoking, said the FDA's moves could send people back to cigarettes.

"The FDA needs to be very cautious about the adverse effects that flavoring bans or excess regulation could have on this trend – smokers using vapor as a way to stop consuming cigarettes and move towards a healthier lifestyle," spokeswoman Liz Mair said.

The companies targeted by FDA struck a conciliatory tone.

JUUL Labs CEO Kevin Burns said the company "will work proactively with FDA in response to its request."

"We are committed to preventing underage use of our product, and we want to be part of the solution in keeping e-cigarettes out of the hands of young people," he said in a statement.

A spokesman for Phillip Morris parent Altria, maker of the MarkTen XL, said the company welcomed the FDA action.

We "look forward to sharing our thoughts about how to prevent and reduce youth use, an issue we have focused on for decades," spokesman David Sutton said.

"We strongly believe kids shouldn’t use any tobacco products and take a number of steps to prevent kids from getting access to all tobacco products," he said.

Anthony Hemsley, Logic's head of corporate affairs, said the company will work with the FDA "to demonstrate that Logic markets its product only to adults."

R.J. Reynolds Vapor, maker of Vuse, said it supports "eliminating youth usage of all tobacco products."

Fontem Ventures, owner of the Blu brand, said it welcomes "the opportunity to demonstrate, and work with the FDA to further strengthen, our youth access prevention policies and procedures. We will continue to work with regulators in the US and elsewhere to implement best practices in all our commercial activities."

In the past, Burns has warned that restricting flavors “will negatively impact current adult smokers” who want to switch from smoking to vaping.

He said the company would support “reasonable regulation” to restrict advertising and the naming of flavors such as cotton candy and gummy bear that target children.

Vaping can also help younger smokers quit.

Spencer Re of Napa Valley, Calif., says he started vaping five years ago as a senior in high school. That led him to start smoking in college. Cigarettes eventually “completely replaced vaping," he said. When he wanted to quit, he says, he turned back to e-cigarettes.

Juul has mounted an aggressive advertising campaign, including full-page ads in newspapers, targeting parents with messages about teen vaping.

The FDA said Wednesday for the first time that some be e-cigarettes might be on the market illegally. Officials said they're investigating some manufacturers for violating rules that require regulators' approval to introduce new products after August 2016. They would not say which companies they are investigating.

Gottlieb said last month that even the 2022 deadline would be a challenge for some manufacturers to meet, so they had "better start now."

"What we’re living through now are the unintended consequences" of Gottlieb's decision to move the compliance date, says Robin Koval, CEO of the Truth Institute. "Congress gave FDA all the authority and FDA has all the tools they need to regulate this market and they need to do this quickly."

She's heartened by Gottlieb's new stance on vaping, but worries that giving companies the chance to tell regulators how they plan to prevent teen vaping is like "asking the proverbial fox to guard the henhouse."

Re says he can't stand the taste of tobacco and cream flavors, so he vaped only fruity flavors.

He thinks the idea that vaping is a "forbidden substance," more than the flavors, is what makes it more attractive to teens.

Jack Cao, who co-owns a chain of vape shops in California, Texas and Virginia, questions whether a ban on the sale of flavored e-liquid would have much impact.

If stores such as his could not sell flavored e-liquid, he said, it would only encourage a new industry of flavors that users themselves would mix with unflavored liquid.

Still, he's been bracing for tougher FDA regulations that could dramatically reduce if not eliminate his vaping business.

He has started a tee shirt business in the back of his Falls Church, Virginia, shop.

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